Conventionally, a dispensing apparatus used in dispensing a liquid sample containing a specimen or a reagent in an analyzing apparatus dispenses a liquid sample by suctioning or draining a liquid, for example, a cleaning liquid, in the pipes with a feeding/draining pump so as to suction the liquid sample through a dispensing nozzle connected to the pipes, and discharging the suctioned liquid sample to a predetermined position. In such a case, if bubbles mix in the cleaning liquid, the dispensing apparatus has a decreased dispensing accuracy for the liquid sample due to the bubbles. Thus, the dispensing apparatus has the pipes filled with a deaerated cleaning liquid.
However, in a case of dispensing for a long period of time, or in a case of replacing parts connected to the pipes in maintenance or the like, slight bubbles may mix in the pipes. In such a case, since it is not easy to find the bubbles, the dispensing apparatus is used with bubbles mixed in, and as a result, analysis is conducted while a dispensing operation is performed with a decreased dispensing accuracy. There has been such a problem.
Thus, in order to solve this problem, a dispensing apparatus having a function of detecting the presence of bubbles in pipes has been proposed (see Patent Document 1).    Patent Document 1: Japanese Laid-Open Publication No. 2003-254982